Condensed Consolidated Statements of Shareholders' Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Purchase of shares of treasury stock (in shares)			26,932	17,590	38,369	75,980
Shares of common stock for the exercise of stock options (in shares)	10,000		68,284	103,608	148,284	260,481
Dividends declared per common share (in dollars per share)	$ 0.12	$ 0.24				$ 0.21
Forfeitures of restricted common shares (in shares)					6,793